TG100

Question 1

where do many of the failures in radiation oncology occur?

Answer 1

errors in workflow and process

Question 2

what is TG100?

Answer 2

application of risk analysis methods to radiation therapy quality management

Question 3

FMEA

Answer 3

failure modes and effects analysis

Question 4

issue with work practises in individual clinics

Answer 4

very variable
not like linacs where there are some standard designs and you can prescribe QA
-have to analyze processes and develop clinic and site specific quality management programs that affect work practises in individual clinics

Question 5

techniques used in TG100

Answer 5

process mapping
FMEA
fault tree analysis

Question 6

3 things included in TG100

Answer 6

(1) the rationale for prospective risk analysis; (2) how to perform process- and clinic-specific risk analysis and quality management program formulation; and (3) a detailed sample application of the method applied to a generic IMRT process

Question 7

does TG100 recommend making sudden big changes to workflow after the analysis?

Answer 7

No, discuss with experts and team first

make sure still compliant with regulations

Question 8

4 recommendations of TG100

Answer 8

• Don’t make sudden large changes to workflow due to results of analysis
• Start with a small project
• Use redundancy
• Quality department at the clinic can likely provide help

Question 9

what happens to physics resource demands as methods become more intensive and complex?

Answer 9

the demand grows

-ex IMRT and OBI QA

Question 10

What is linked to serious errors in some radiation therapy accidents?

Answer 10

mental and physical overload

Question 11

what is not meeting the desired level of quality?

Answer 11

failure

Question 12

definition of quality

Answer 12

Those features which meet the needs of the patient,including rational medical, psychological, and eco-nomic goals while also taking into account the profes-sional and economic needs of the caregivers and theinstitution.
•A clinical process that is designed to realize cancer treat-ments that conform with nationally accepted standardsof practice and specifications; and
•Freedom from errors and mistakes

Question 13

define error

Answer 13

failures consisting of acts, either of commission(doing something that should not have been done)or omission (not doing something that should have been done), that incorrectly execute the intended action required by the process

Question 14

define mistakes

Answer 14

failures due to incorrect intentions or plans, such that even if executed as intended would not achieve the goal

Question 15

define violations

Answer 15

failures due to intentionally not followingproper procedures, either as shortcuts with the intentionof achieving the correct goal or sabotage

Question 16

define event

Answer 16

the entire scenario, including the failure it-self and its propagation through the clinical pro-cess, resulting in a patient treatment of diminished quality

Question 17

define near-event

Answer 17

a situation resulting from a failure that would have compromised quality of the patient’s treat-ment had it not been detected and corrected. Also known as close call, near miss, and good catch

Question 18

types of failures

Answer 18

human
equipment
organizational or design (latent)

Question 19

what is essential performance

Answer 19

defined by the International Electrotechnical Commission (IEC) as the performance neces-sary to achieve freedom from unacceptable risk

Question 20

risk mangement

Answer 20

systematic application of management policies, procedures, and practices to the tasks of analyzing,evaluating, and controlling risk

Question 21

risk assessment

Answer 21

considers the way in which the quality of treatments can fail to achieve the desired goals

Question 22

4 components of quality management

Answer 22

quality planning
quality control
quality assurance
quality improvement

Question 23

difference between QC and QA

Answer 23

QC maintains integrity of process
QA provides confidence that the output of the process is correct

i.e. QC is about input and QA about outpout

for example, QC failure would be not realizing a system is using the wrong calculation algorithm. QA failure would be not seeing that the calculated result is incorrect

QC usually requires more resources than QA

Question 24

RCA

Answer 24

root cause analysis
reactive approach to safety (once an incident occured or almost occurred)
-focuses on systems and processes rather than individual blame

Question 25

safety barriers

Answer 25

critical control points

any process steps whose primary function is to prevent errors or mistakes from occurring or propagating through the radiotherapy workflow

Question 26

prospective risk analysis

Answer 26

goal is to identify risky process steps before a failure happens

Question 27

overview of FMEA

Answer 27

it moves through the process and considers, for each step, what could fail, how it could fail, what is the likelihood of failure, what is the likelihood that a failure would not be detected, and what the effects of failure would be. The overall risk of each identified failure mode is then scored, so that these failure modes can be prioritized

Question 28

overview of fault tree analysis

Answer 28

evaluates the propagation of failures

Question 29

order of steps in TG 100

Answer 29

• process mapping
• FMEA assess all potential risks
• FTA evaluates propagation of failures
• QM program is developed based on how to best avoid the faults and risks identified

Question 30

the team for TG-100

Answer 30

multi-disciplinary

Question 31

three parameters in FMEA

Answer 31

• O(occurrence) describes the likelihood that a particular cause for the specified failure mode exists.
• S(severity) describes the severity of the effect on the final process outcome resulting from the failure mode if it is not detected or corrected.
• D(lack of detectability) describes the likelihood that the failure will not be detected in time to prevent an event.

they range from 1-10

While past experience with QC or patient outcome studies might be available to guide the choice of the value for D, its selection will rely largely on expert opinion

Question 32

RPN

Answer 32

Risk priority number in FMEA

RPN = OSD

Question 33

ranges of OSD

Answer 33

Oranges from 1 (failure unlikely,<0.01%) to 10 (failure likelihood is substantial, more than 5% of the time).
•S ranges from 1 (no danger, minimal disturbance of clinical routine) to 10 (catastrophic, whether from a single event or accumulated events)
•D ranges from 1 (very detectable: 0.01% or fewer of the events go undetected throughout treatment) to 10 (very hard to detect,>20% of the failures persist through the treatment course).

Question 34

as S increases, what happens to D?

Answer 34

typically more severe issues (such as horrid coverage) become more likely to be detected)

Question 35

ranking of QM tools from most effective to least effective

Answer 35

most effective: forcing functions and constraints (interlocks)

2. automation
3. protocols (i.e. checklists)
4. independent double-checks and other redundancies
5. rules and policies
6. education

Question 36

common themes on safety and quality in RO

Answer 36

training, documen-tation, communication, and both reactive and prospective approaches to error management

Question 37

issue with estimating detection rate

Answer 37

few studies document this

Question 38

dominant cause of failure

Answer 38

human failure

Question 39

highest ranking hazard in TG100 IMRT example

Answer 39

incorrect interpretation of a pre-treatment disgnostic image for defining the GTV

-peer review is most effective QM step

2nd highest ranked hazard was bad delineation of GTV (similar issue)

Question 40

key quality compoennets identified

Answer 40

-Standardized procedures.
•Adequate training of staff.
•Clear lines of communication among staff.
-Maintenance of hardware and software resources.
•Adequate staff, physical and computer resources.